1. Field of the Invention
The present invention relates generally to a blade exchanging device and a blade exchanging method therefor in order to exchange a blade of a dicing machine, which dices a semiconductor wafer.
2. Description of Related Art
A dicing machine rotates a blade at a high speed and dices a semiconductor wafer, on which many chips are formed, along the chips. In the dicing machine, the blade is fastened on a spindle with a nut, and a special blade exchanging device is used for exchanging the blade.
A conventional blade exchanging device comprises a cylindrical spanner and a sticklike torque wrench. The operator engages the spanner with the nut, and then inserts the torque wrench through a hole of the spanner so that a polygonal head of the torque wrench is engaged with a polygonal hole formed in the head of the spindle. In this state, the operator securely holds the torque wrench by one hand to prevent the wrench from rotating, and rotates the spanner by the other hand to unfasten the nut. The nut is thereby detached from the spindle. After disengaging the spanner from the spindle, the old blade is dismounted from the spindle and a new blade is mounted on the spindle. Then, the operator puts the nut on the spindle with the spanner, and rotates the spindle with the torque wrench so that the nut is fastened on the spindle. An operation for exchanging the blade using the blade exchanging device is completed by the above-described process.
However, in the conventional blade exchanging device, the nut may fall off the spanner when detaching the nut from the spindle and disengaging the spanner from the spindle. Moreover, the blade exchanging device requires the operator to use both hands, and the operator must insert both hands into a narrow space when the blade is in the narrow space, which is difficult. The blade exchanging hence used to be a troublesome operation.
The present invention has been developed in view of the above-described circumstances, and has as its object the provision of the blade exchanging device and the blade exchanging method therefor by which the nut is prevented from falling off the body of the exchanging device, and the operator can perform the exchanging operation manually with only one hand.
In order to achieve the above-described objects, the present invention is directed to a blade exchanging device with which at least one of unfastening of a blade, the blade being fastened to a spindle with a nut, from the spindle by unfastening the nut from the spindle and fastening of the blade to the spindle by fastening the nut to the spindle is performed, the blade exchanging device comprising: a cylindrical body which is engaged with the nut; a chuck which is provided inside the cylindrical body and is fitted with a fitting portion formed on the nut so as to hold the nut; and a wrench which is inserted through a hole of the chuck so as to be engaged with a hole formed in a head of the spindle, wherein one of the spindle and the nut is prevented from rotating while the other of the spindle and the nut is rotated with the wrench and the cylindrical body to perform at least one of unfastening of the nut from the spindle and fastening of the nut to the spindle.
According to the present invention, the body of the exchanging device is first engaged with the nut that is fastened to the spindle while fitting the chuck into the fitting portion that is formed on the nut so as to hold the nut. Second, the wrench is inserted through the hole of the chuck and the head of the wrench is engaged with the polygonal hole formed in the head of the spindle. In this state, one of the spindle and the nut is prevented from rotating while the other of the spindle and the nut is rotated with the wrench and the cylindrical body so as to unfasten the nut, whereby the nut is detached from the spindle. When the body of the exchanging device is detached from the spindle, the nut does not fall off the body of the exchanging device since the nut is held at the chuck. Thus, the blade exchanging device of the present invention can prevent the nut from falling off the body of the exchanging device.
Moreover, according to the present invention, the nut is held without falling off the body of the exchanging device by fitting the chuck provided to the body of the exchanging device into the fitting portion formed at the nut. Next, the nut is pressed against the body of the exchanging device while inserting the wrench through the hole of the chuck so as to engage the head of the wrench with the polygonal hole formed in the head of the spindle. Then, one of the spindle and the nut is prevented from rotating while the other of the spindle and the nut is rotated with the wrench and the cylindrical body, whereby the nut is fastened to the spindle. In this state of fastening the nut, the nut can be easily fastened since it is held by the chuck without falling off the body of the exchanging device.
Further, the blade exchanging device of the present invention is constructed in such a manner that the cylindrical body and the nut are engaged with each other by a projection and a depression provided on a circle coaxial with the spindle. Thus, the projection and the depression can be engaged with each other by only rotating either one of the body of the exchanging device or the nut with the wrench, even though in a case where the projection and the depression do not engage with each other when pressing the body of the exchanging device against the nut.
Furthermore, in the blade exchanging device of the present invention, the cylindrical body is attached to a fixed member provided nearby the blade through an arm member so as to be able to swivel, and the cylindrical body is pressed by a pressing member in a direction so that the nut is pressed against the spindle.
In such a blade exchanging device, the body of the exchanging device is first attached to the cover of the blade and at the same time is pressed against the nut with the pressing force of the pressing member. Next, the chuck is operated so as to hold the nut. Then, the wrench is inserted through the hole of the chuck and the head of the wrench is engaged with the polygonal hole of the spindle. Subsequently, the spindle is rotated by the wrench in the direction to loosen the nut, whereby the nut is detached from the spindle. Thereafter, the body of the exchanging device is retracted from the blade by swiveling the body of the exchanging device via the arm. In this state, since the nut is held by the chuck, the nut does not fall off the body of the exchanging device. Then, an old blade is detached from the spindle and a new blade is attached to the spindle. The body of the exchanging device is swiveled via the arm so as to position the body at the position facing to the spindle, and the nut held at the chuck is pressed against the spindle by the pressing force of the pressing member. After that, the spindle is rotated in the direction to fasten the nut. Thus, the nut is fastened to the spindle and the new blade is fixed to the spindle. Then, the chuck is operated so as to release the holding of the nut by the chuck. The body of the exchanging device is detached from the blade cover member. The blade exchanging operation is completed by the above-described manner, which is performed by the operator with only one hand.